A review: Simultaneous "one-pot" pollution mitigation and hydrogen production from industrial wastewater using photoelectrocatalysis process

This review delves into the underlying principles, advantages, challenges, and recent developments in photoelectrocatalysis (PEC) processes for wastewater treatment and green hydrogen production. PEC is an emerging technique that holds great promise for addressing two critical challenges simultaneously, namely, the degradation of industrial wastewater pollutants and the generation of clean energy in the form of hydrogen gas. In recent years, many studies have explored the use of photoanodes to harness solar energy for wastewater treatment. These photoanodes facilitate the breakdown of contaminants, while the cathode concurrently produces green hydrogen. The PEC enables the production of both clean water and hydrogen gas from industrial wastewater. This dual benefit makes it an attractive avenue for sustainable industrial wastewater treatment and clean energy generation. The PEC process capitalizes on the constructive interaction between electrochemical reactions and photocatalysis. Solar energy is efficiently converted into electron-hole pairs, which play a pivotal role in water-splitting reactions occurring at the electrode surfaces. Achieving the best performance involves scrutiny of various parameters, including catalyst loading, pH, light intensity, and electrolyte composition. The photoelectrocatalytic system shows commendable stability and durability during extended operation, reinforcing its practical applicability. This review provides a comprehensive overview of the PEC process, catalyst materials, optimization strategies, and driving efficiency. Considering the potential benefits and costs on a larger scale underscores the significance of photoelectrocatalytic hydrogen production in addressing environmental concerns and energy-related issues concurrently. Therefore, PEC is a promising pathway toward sustainable water treatment and clean energy, bridging the gap between environmental stewardship and technological advancement.